Specifies the address of a variable receive the value of pname​ for attachment​.

Description

glGetFramebufferAttachmentParameter returns information about attachments of a bound framebuffer object. target​ specifies the framebuffer binding point and must be GL_DRAW_FRAMEBUFFER, GL_READ_FRAMEBUFFER or GL_FRAMEBUFFER. GL_FRAMEBUFFER is equivalent to GL_DRAW_FRAMEBUFFER.

If the default framebuffer is bound to target​ then attachment​ must be one of GL_FRONT_LEFT, GL_FRONT_RIGHT, GL_BACK_LEFT, or GL_BACK_RIGHT, identifying a color buffer, GL_DEPTH, identifying the depth buffer, or GL_STENCIL, identifying the stencil buffer.

If a framebuffer object is bound, then attachment​ must be one of GL_COLOR_ATTACHMENTi, GL_DEPTH_ATTACHMENT, GL_STENCIL_ATTACHMENT, or GL_DEPTH_STENCIL_ATTACHMENT. i in GL_COLOR_ATTACHMENTi must be in the range zero to the value of GL_MAX_COLOR_ATTACHMENTS - 1.

If attachment​ is GL_DEPTH_STENCIL_ATTACHMENT and different objects are bound to the depth and stencil attachment points of target​ the query will fail. If the same object is bound to both attachment points, information about that object will be returned.

Upon successful return from glGetFramebufferAttachmentParameteriv, if pname​ is GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, then params​ will contain one of GL_NONE, GL_FRAMEBUFFER_DEFAULT, GL_TEXTURE, or GL_RENDERBUFFER, identifying the type of object which contains the attached image. Other values accepted for pname​ depend on the type of object, as described below.

If the value of GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is GL_NONE, no framebuffer is bound to target​. In this case querying pname​GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME will return zero, and all other queries will generate an error.

If the value of GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is not GL_NONE, these queries apply to all other framebuffer types:

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE, GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE, GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE, GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE, GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE, or GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE, then params​ will contain the number of bits in the corresponding red, green, blue, alpha, depth, or stencil component of the specified attachment. Zero is returned if the requested component is not present in attachment​.

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE, params​ will contain the format of components of the specified attachment, one of GL_FLOAT, GL_INT​, GL_UNSIGNED_INT​, GL_SIGNED_NORMALIZED​, or GL_UNSIGNED_NORMALIZED​ for floating-point, signed integer, unsigned integer, signed normalized fixed-point, or unsigned normalized fixed-point components respectively. Only color buffers may have integer components.

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING, param​ will contain the encoding of components of the specified attachment, one of GL_LINEAR or GL_SRGB for linear or sRGB-encoded components, respectively. Only color buffer components may be sRGB-encoded; such components are treated as described in sections 4.1.7 and 4.1.8. For the default framebuffer, color encoding is determined by the implementation. For framebuffer objects, components are sRGB-encoded if the internal format of a color attachment is one of the color-renderable SRGB formats.

If the value of GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is GL_RENDERBUFFER, then:

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, params​ will contain the name of the renderbuffer object which contains the attached image.

If the value of GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is GL_TEXTURE, then:

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, then params​ will contain the name of the texture object which contains the attached image.

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL, then params​ will contain the mipmap level of the texture object which contains the attached image.

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE and the texture object named GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME is a cube map texture, then params​ will contain the cube map face of the cubemap texture object which contains the attached image. Otherwise params​ will contain the value zero.

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER and the texture object named GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME is a layer of a three-dimensional texture or a one-or two-dimensional array texture, then params​ will contain the number of the texture layer which contains the attached image. Otherwise params​ will contain the value zero.

If pname​ is GL_FRAMEBUFFER_ATTACHMENT_LAYERED, then params​ will contain GL_TRUE if an entire level of a three-dimesional texture, cube map texture, or one-or two-dimensional array texture is attached. Otherwise, params​ will contain GL_FALSE.

Any combinations of framebuffer type and pname​ not described above will generate an error.

Errors

GL_INVALID_ENUM is generated if target​ is not one of the accepted tokens.

GL_INVALID_ENUM is generated if pname​ is not valid for the value of GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE.

GL_INVALID_OPERATION is generated if attachment​ is not the accepted values for target​.

GL_INVALID_OPERATION is generated if attachment​ is GL_DEPTH_STENCIL_ATTACHMENT and different objects are bound to the depth and stencil attachment points of target​.

GL_INVALID_OPERATION is generated if the value of GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is GL_NONE and pname​ is not GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME.